.5

SS-2.1.2 Strength

.1

The roof framing and decking shall be designed
of sufficient strength so that they will support the anticipated
load such as construction loads. Roof decks shall be free of
damaged, deteriorated or decayed wood.

SS-2.1.3 Surface

.1

The surface of all roof decks to which a roofing
system is to be applied shall be sufficiently clean and dry so that
proper attachment can take place.

.2

Roofing over existing asphalt shingles is not
permitted, tear off old materials to expose the decking.

.3

Repair damaged or deteriorated decking and fill
abandoned deck openings with similar materials prior to
reroofing.

.2

SS-2.2 Roofing Materials

SS-2.2.1 General

.1

The roofing materials shall conform to the
Alberta Building Code (A.B.C.) and shall comply with their
applicable materials standard.

.2

Materials shall be adequately labeled so that
proper identification of the materials may be made.

SS-2.2.2 Protection and Storage

.1

All roofing materials that can be adversely
affected by moisture shall be protected prior to application and
only dry materials shall be applied.

.2

Rolls of felt are to be stored on end, covered
and out of danger of water penetration.

SS-2.2.3 Application Limitations

.1

No roofing material is to be applied when the
weather or the condition of its substrate is such that the required
installation procedures could not be followed or which would
jeopardize the performance of the roofing system or the safety of
the applicators.

SS-2.2.4 Asphalt Shingles

.1

Inorganic asphalt shingles shall conform to CSA
A123.5-98, Asphalt Shingles made from glass felt and surfaced with
mineral granules. Shingles may be three-tab or laminate.

SS-2.2.5 Organic Felt

.1

The organic felt used for the underlayment and
eave protection shall be No.15 asphalt saturated non-perforated
felt conforming to CSA A 123.3-98.

SS-2.3.2 Valley Flashing

.1

Revised

2010-06

.2

Open valleys must be employed for
laminated asphalt shingle applications.

Revised

2016-04

.3

Where sloping surfaces of shingle roofs
intersect to form a valley, the valley shall be flashed with a
minimum of one (1) ply of 914mm (36”) wide self adhering modified
bituminous membrane centered in valley.

.4

Open valleys shall be flashed with an additional
layer of sheet metal not less than 600 mm (2 ft.) wide. Where
adjoining roof areas differ in pitch, the metal valley flashing
shall contain a 25 mm (1”) high centre crimp.

.5

The shingle underlayment shall be carried over
(on top of) the edges of the sheet metal valley flashing and be
trimmed to a line parallel to the interior cut edge of the
shingle’s triangular clip. Shingles and shingle segments on both
sides of valleys shall have their top valley edge clipped to form
an approximately 50mm (2”) wide triangle to direct runoff towards
the valley’s centerline.

.6

For woven and closed cut valleys, shingles shall
be tightly pressed into the valley and fastened no closer than
150mm (6") from the valley centre line. Shingle terminations on
opposite sides of the valley shall be fastened with a minimum of
two (2) roofing nails placed vertically above one another.

.7

For closed cut valleys, trim the overlapping
shingles at a minimum distance of 50mm (2") up/back from the valley
centerline.

SS-2.3.3 Intersection of Shingle Roofs
and Walls

.1

The intersection of shingle roofs and walls or
chimneys shall be protected with flashing in accordance with the
Alberta Building Code (A.B.C.).

.2

Sheet metal step flashing shall be installed
when the rake of a roof abuts a vertical wall or projection.

SS-2.3.4 Chimney Saddles

.1

For sloping roofs, chimney saddles shall be
installed where the upslope side of a chimney is more than 762mm
(30”) wide. See the Alberta Building Code for details.

.2

For chimneys less than 762mm (30”) wide,
a chimney saddle need not be installed if the intersection between
the chimney and roof decking is protected by one (1) ply of
self-adhering modified bituminous membrane covered by a sheet metal
flashing (back pan) that extends up the chimney to a height equal
to not less than one sixth the width of the chimney, but no less
than 150mm (6”) in height and shall extend up the roof slope to a
point equal in height to the top edge of the chimney flashing, but
not less than 1.5 times the shingle exposure.

Revised

2010-06

.3

Chimney saddles and valleys shall be treated in
accordance with Clause 2.3.2.

SS-2.4 Eave Protection and Metal
Flashing

SS-2.4.1 Eave Protection

.1

Eave protection shall extend from the roof edge
a minimum distance of 900mm (3 ft.) up the roof slope to a line not
less than 300mm (1 ft.) inside the inner face of the exterior
wall.

.2

Eave protection is not required:

Over unheated garages, carports and porches,

Where the roof overhang exceeds 900mm (3 ft.) measured along
the roof slope from the edge of the roof to the inner face of the
exterior wall,

On roofs with slopes of 8:12 (1:1.5) or greater.

SS-2.4.2 Materials

.1

Eave protection laid beneath the starter strip
shall consist of one of the following:

Type M or S roll roofing conforming to CSA A123.2-M1979, laid
with not less than 100mm (4”) head and end laps cemented together
with lap cement. This application is restricted to warm weather
applications to minimize the possibility of wrinkling.

Minimum No. 25 glass fiber coated base sheets,

Self-adhering modified bituminous membranes.

SS-2.4.3 Drip Edge Flashing

.1

Pre-finished or galvanized sheet metal
drip edge flashing shall be installed along roof eaves and rakes.
The vertical flange shall be spaced a minimum distance of 6.4mm
(1/4”) from the fascia face. The deck flange shall extend a minimum
distance of 75mm (3”) on to the roof decking and shall be nailed at
maximum 400mm (16”) centres prior to shingle application.

Revised

2010-06

.2

At the eaves, the sheet metal drip edge flashing
shall be fastened directly to the roof decking beneath the eave
protection.

.3

At roof rake edges, the drip edge shall be
fastened to the roof decking over the underlayment and eave
protection membranes.

.4

Exposed flashing edges shall be hemmed.

SS-2.5 Underlayment

SS-2.5.1 Materials

.1

The field of the decking shall be completely
covered with a minimum of one (1) ply of CSA No. 15 non-perforated
asphalt saturated felt prior to application of the shingles.

SS-2.5.2 Installation

.1

Underlay shall be installed parallel to the
eaves with head and end lap of not less than 100mm (4”).

.2

The underlay shall overlap the eave protection a
minimum distance of 100mm (4”).

.3

The top edge of each underlayment strip shall be
sufficiently fastened to hold the underlayment in place until the
shingles are applied.

.4

Ensure the underlayment is lying flat prior to
shingle application.

SS-2.6 Ventilation

.1

Every roof space or attic above an insulated
ceiling shall be ventilated with openings to the exterior to
provide an unobstructed vent area of not less than 1/300 of the
insulated ceiling area. Vents may be roof type, eave type, soffit
type, gable-end type or any combination thereof, and shall be
uniformly distributed on opposite sides of the building. Roof vents
shall be equally distributed so that approximately 50 percent of
the required vent area is located near the lower part of the roof
and approximately 50 percent of the required vent area is near the
ridge. For exceptions see Alberta Building Code, Section 9.19.1,
Venting.

SS-2.7 Application

SS-2.7.1 Coverage

.1

Coverage shall be not less than two (2)
thicknesses of asphalt shingles over the entire field of the roof,
disregarding three tab shingle cutouts.

SS-2.7.2 Starter Strip

.1

A starter strip shall be installed along the
lower edge of the roof so that it extends approximately 19.0mm
(3/4”) beyond the eaves and rakes of the roof and be fastened along
the bottom edge with nails spaced not more than 300mm (1 ft.) on
centre.

.2

Starter strips shall be three (3) tab shingles
with tabs facing up the roof slope or starter shingles of the same
weight and quality as those used as the roof covering.

SS-2.7.3 Head Lap

.1

Shingles shall have a head lap of not less than
50mm (2”).

SS-2.7.4 Fasteners

.1

Shingles shall be fastened with no fewer
than four (4) roofing nails per shingle, placed in the nailing zone
so that nails penetrate through both shingle courses and the roof
decking, with no exposed nails. Nails shall be driven flush with
the shingle surface.

Revised

2010-06

.2

For roof pitches greater than 12:12, asphalt
shingles shall be fastened with a minimum of six (6) roofing nails
per shingle.

.3

Fasteners shall be located 25mm (1”) to 38mm
(1-1/2”) from the end of each shingle and the remaining fasteners
equally spaced between them.

.4

For three tab shingles, roofing nails shall be
located not less than 12.7mm (1/2”) above the tops of the
cutouts.

.5

Fastener quantities may be reduced for
trimmed shingles in proportion to the shingle segment’s width. No
fewer than two (2) roofing nails shall be used to secure trimmed
shingle segments.

Revised

2016-04

.6

No nail head shall be left exposed to the
weather.

SS-2.7.5 Securing of Tabs

.1

Shingles and shingle tabs shall be
secured by a self sealing adhesive strip or by additional
application of plastic cement when hand tabbing.

Revised

2015-03

.2

Follow shingle manufacturer's
application recommendations and allow one (1) season for shingles
to seal. Shingles shall be hand tabbed during cold weather
applications in accordance with manufacturers
recommendations.

Revised

2016-12

.3

The first course of shingles shall be hand
tabbed to the starter shingles along eave and rake edges.

.4

SS-2.7.6 Hips and Ridges

.1

Hip and ridge shingles must be applied so they
extend not less than 100mm (4”) on either side of the hip or ridge
centre line and shall be lapped not less than 150mm (6”). Shingle
laps shall face away from the prevailing wind direction.

.2

Shingles must be fastened with nails located not
more than 25mm (1”) from the edge and 25mm (1”) above the butt of
the overlying shingle on both sides of the hip or ridge centre
line.

SS-2.8 Accepted Asphalt Shingles

SS-2.8.1 Organic Asphalt Shingles

Organic Asphalt
Shingles are no longer manufactured or available in
Canada